Sighting device



Patented Sept. 19, 1944 'l l carica sIGn'rlNG Evicn Morton L. E. Chwalow, Philadelphia, Pa.

Application July 20, 1942, Serial No. 451,663

My invention relates to sighting devices and in particular to the type in which an image of a sight pattern is superimposed upon a target in a line of sight established by the user through the device. Sighting devices of this atype are not new, several different structures being illustrated in issued patents such as, for'example, the Grubb patent, 683,203. A It is believed, however, that the particular@x optical arrangement employed in my device represents a meritorious advance in the art since it permits a structure which is extremely simple in design, easy to service, and economical to manufacture.

Jn my arrangement I employ a transparent 16 meinberhaving a plane face supported at an angle to the user through which a line of sight to a target may be established by the user.

A sight pattern and a concave reiiector are dis- Light passing through the sight pattern and inclined face of the transparent member to the reflector will be reflected back onto the inclined face, and thence into the eye of the user. This optical arrangement produces an image of the sight pattern superimposed upon the target and the image appears to the user to be at thesame distance from him as is the target.

tion may be supported upon a pelorus base and used to measure the drift angle of an aircraft by The principles of my invention may also be utilized i'n the optical `system for other sighting devices such as a gun sight, bomb 'estimating device.

In the drawing, which represents a preferred 4:. embodiment of my invention, and in which llike,

rug), T

sight, or range parts in the various views are designated byglike reference characters: 1

Fig. l is a sectional view of the device;

Fig. 2 is a view in elevation;

Fig. 3 is a sectional view on lines Fig. 1, showing the sight pattern;

Fig. 4 is a view on' lines 4 4 of Fig. 2, illustrating how lters for the sight may be swung into and out of use;

Fig. 5 is an end view of the eyepiece; and

Fig. 6 is a diagrammatic view illustrating 'the optical arrangement employed in the device.

Referring now to the drawing, the body of the l device consists of a pair of sections I and 2 which may be made of any suitable material such as collars 2| and 22.

z claims. (ci. ss-i) (Granted under the act of March 3, 1883, as

amended April 30, 1928; i370 0. G. 757) l y metal or a moldedplastic. Section I consists of' a pair of tubular portions 3 and 4 which inter- Y sect at a right angle. 'Iubular portions 3 and 4 arcut ofi' at an angle of 45 at their intersection which forms an annulus of elliptical contour. 1

Section2 likewise consists of a pair of tubular `portions 5 and 6 intersecting at a right angle and cut oil to form an elliptical annulus at their intersection which is at an angle of lIn order to unite sections I and 2, elliptical colf lars 1 and 8 may be provided respectively for the sections. Collar 'I fixed to section I contains an ellipticalrecess 9 on one side which ts over and is secured to the elliptical annulus of section I. A second recess I0, also elliptical, on the opposite side, is provided for partially seating a at transparent member I I which may be made of crown glass. A face of member II may be provided wlth a very thin semi-transparent layer of reilec'ting material 46 such as silver to increase the reflectivity of the face. This layer is not, however, essential to the operation of my device.

Collar 8 fixed to section 2 likewise contains an elliptical recess I2 for iitting over the elliptical` annulus of section 2 and a second recess I3 for seating the transparent member II.

Collars 1 and 8, of course, need not be made separately but may be made integral 'with sections I and 2 if the latter are molded or cast. A device made in accordance with my inven- Collars 'l and 8 (and hence sections I and 2) e is disposed coaxially withtubular member 5..

Likewise tubular members 4 and 6 are disposed coaxially and at right angles tothe axis of tubular members 3 and 5.

An eyepiece I5 which may be of softrubbfis T fitted to the end 'of tubular portion 3 by cement or any other suitable means.

'I ubular portion l is threaded externally at thev e'id for receiving an internally threaded cap member IB. Cap I6 houses a concave reflector II which is supported in a threaded collar I8, the latter being screwed down in the cap until it and the back of reflector I1 abuts a cushion I9 which may be made of felt or other suitable material. Reflector I1 may be spherical crit may be parabolic. In either case, however, for best results, the sight pattern described below should be at the focus of the reflector.

A holder 44 which is threaded internally and contains 'an internal shoulder 20 is provided for seating a pair of externally threaded annular ing intosthe device from the target for purposesfor Joining said body sections together with the Z y 2,358,316 I Collar 2l supports a transparent member 2l, particular device described is but a preferred one face of which is co'ated with opaque material embodiment of my invention and that changes (L 45 such as black paint. The sight pattern conand modifications therein may occur to those sists oi a pair of slits 24 and 2E cut into the skilled in the art without departing from the opaque material at right angles to each other. spirit andscope oi' my invention, as deilned in If the device is used for a gun sight, the design',I the appended claims. f of the sight pattern might be a pair of con" The invention described herein may be manucentric rings in which case a pair of concentrici factured and used bv or for the Government of slits would be provided in the coating 45. the United States for governmental purposes Collar 22 supports a diiusing screen 28 which. l@ without the payment of any royalties thereon or serves to diffuse the light entering the slits 24 therefor. and 25. Having thus described my invention, I claim:

Holder 44 supporting member 23 and diffusing 1. In a sighting device the combination comscreen 28 is then seated at the end of tubular prising a pair of body sections, each section com- 1 member 6 and secured in position by a plurality l5 prising a pair of tubular portions intersecting at oi' screws 21. a right angle and cut on a 45 diagonal at their In order to vary the intensity o! the light comintersection to form an elliptical opening, means of obtaining a goed contrast between the illumielliptical openings therein adjacent each other,

natedjmage 0f the sight pattern and the target, 20 a transparent' member having a plane face disiilter such as the three filters 28, 2S and 3U may posed at the intersection of said body sections be utilized. at an angle of 45, an eyepiece disposed on one Filters 28 to 3l! are seated respectively in tubular portion of one of said body sections, so

frames 3l to 33 and secured therein by retaining that the user may establish e. line of sight therewashers 34 to 36. 255, through and through the coaxially disposed tu Frame members 3|, 32 and 33 are each pro- .,bular portion in the other of said body sections vided with an ear portion which is bored so that to a, target, 9, sight pattern, and a concave re- ,f

the frames may be plvotally mounted 0n a pivot nectar, said sight pattern and reflector being dispin 37 which iS Carried by a bracket 33, the ltposed respectively on opposite sides of said transter being fastened to the exterior surface of tu'. 30 parent member in the other two remaining tu bular section 5 by means 0f SCI'BWS 39. bular portions whereby light passing through As clearly seen from Fie. 4, the frames con' said sight pattern and plane face ofsaid Vtranstaining the illters may be swung into and out of parent, member to said raged-,0r wm be reflected position for filtering as the needs require back'ontc said piane face and thence intc the Referring 110W to Fig. 6. my improved device 35 users eye forming an image of said sight patoperates in the following manner: tem superimposed upon said target.

Some 0f the light rays Passing through 51155 2. In a sighting device, the combination corny "if". 24 and 25 Wm be reflected outwardly through prising a pair of body sections, each section comtubular portion 5 by the inclined face Of trims' prising a pair of tubular members intersecting parent member Il and will be lost. However, 4o at a right angle and cut on a 45 diagonal at others of such rays (illustrated by rays 40 and their intersect-,1mi to form an opening, means for 4I in Fig. 6) will pass on through member Il joining said body sections together with the and Semi'transparent layer 45- These mys Wm v,openings therein adjacent each other to formV Strike the concave surface of reflector Il and, two airs of axial] au n d tub 1 because slits 24 and 25 are situated at the focus 45 plan) transparent remere dispoeranbitse'r' of the reflector, the rays will be reflected paralsection of said body sections' one pan. of axially I lel as shown. These parallel rays striking the inaligned tubular members serving to permit the i cllned face of transparent member Il and layer riser of the device to establish a line of sight 46 will be reflected into the eye 0i' the User t0 therethrough to a target, a sight pattern, and form a luminous image of the slits 24 and 25' n collimating means, said sight pattern and colliwhich image appears superimposed upon the tar- I mating means being disposed on opposite sides get Which the User Sees by direct Vision (U1US of said transparent member in the other pair oi' Hated by rays 42 and 43) through transparent axially aligned tubular members, whereby light member Il and semi-transparent layer 4B. M passing through said sight pattern and-trans- In the event that a more brilliant image of the parent member to said collimating means wm sight pattern is desired, a small lamp may be be reflected back onto said transparent member i placed adjacent the diffusing screen 28 in a manand thence into the user-'s eyes forming an image v, nersimilar tothat illustrated in the aforemenof said sight pattern superimposed uponrsaid y tiOIled Grubb paf/ent. target I MAQ In conclusion, I wish to point out Athat the 60 Y MORTN L. E. CHWALOW. 

